In a confidential report published in the Guardian today, Mr de Soto criticised the international boycott imposed after Hamas won elections, which he argues contributed to the current crisis.

'The steps taken by the international community with the presumed purpose of bringing about a Palestinian entity that will live in peace with its neighbour, Israel have had precisely the opposite effect,' he wrote.

The US and Israel had both erred in seeing Hamas as a passing phenomenon, the envoy argued. 'Erroneous treatment of Hamas could have repercussions far beyond the Palestinian territories because of its links to the Muslim Brotherhood, whose millions of supporters... might conclude that peaceful and democratic means are not the way to go,' he wrote."